COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 3100 (Jetstream) Series Aeroplanes AD/JETSTREAM/37 Brake Master Cylinder Mounting Assembly Applicability: Model 3100 and 3200 with constructors numbers 601 to 870. Requirement: Action in accordance with BAe Alert SB 27-A-JA 880145. Compliance: Effective forthwith, in accordance with the Requirement Document. 9/90 DM Background: There has been a report of cracking of the brake master cylinder lower mounting bracket. Failure of the bracket would result in loss of braking on the affected wheel.